Why are Democrats in disarray?

Facing big test votes this week on the Reagan budget, the Democrats appear in disarray, unable to rally to their leadeship's uncertain trumpet. The Democratic leader in the Senate, Robert C. Byrd of West Virginia, as much as conceded the ground when he said May 2 he would vote with the Republicans on the budget, saying the public wants to give President Reagan a chance.

In the House, Democratic Speaker Thomas P. O'Neill Jr. of Massachusetts has waxed both despondent and bold, leaving a confused trail for his party's House members to follow in a vote to cut spending half as much as Mr. Reagan wants.

The Democrats say they have two strategies. First, the President's popularity is so high after the attempt on his life, they will give him room for now. The House budget resolution, to be voted on this week, is not binding and can be changed in the Democratic-controlled committees. The tax bills, to come up later, are the real test, they claim.

Second, the Democrats argue the President's economic package is flawed, will not work and will sow the seeds of its own failure. Disenchantment then will set in with the Reagan regime over social issues like abortion and school prayer.

This laid-back style disturbs the Democratic leadership's critics.

"The current Democratic syndrome -- 'Let him have everything he wants, we'll pick up the pieces after he's failed' -- is a massive failure on the part of the Democratic leadership on the Hill and in the party," says Leon Shull, executive director of Americans for Democratic Action.

"Me-tooing the President is no way back to political power.

"Privately, the Democrats on the hill say Reagan's program is madness," Mr. Shull says. "But publicly they go along with it. It's very sad. I have more respect for the Republican Party leadership. At least over the years they stood up against the Democrats and fought."

Senator Byrd's early capitulation on the budget is seen as an attempt to protect himself on his conservative flank if he runs again for a Senate leadership role. He has been criticized both from the right and from the left, and can expect a challenge from both quarters.

But such concessions leave President Reagan all the more the man alone in the spotlight. The absence of Democratic command makes it easier for soft party support in the public to attach itself to the GOP. The CBS-New York Times poll reported May 2 a shift in party identification toward the Republicans. In a January 1980 CBS-NYT poll, 53 percent of those polled considered themselves Democrats, 33 percent Republicans. In the latest poll, conducted April 22-26, the Democratic margin was 49 percent to 41 percent.

But Reagan's personal appeal and Republican gains among voters explain the kind of Democratic leadership withdrawal witnessed in Washington, suggests Everett Ladd, director of the Roper Center at the University of Connecticut in Storrs, Conn.

The evidence on Republican voter gains is mixed. Republican pollster Richard Wirthlin and the CBS poll show GOP gains, Mr. Ladd says, but other polls -- by Gallup and Roper, for example -- show no gain or a statistically inconclusive two- or three-point gain. Yankelovich showed a slight Democratic gain.

"We're witnessing either a mild, historically precedented shift for the Republicans, or a muddy picture," says Ladd. "Over the last 40 years, voter allegiance had bounded here and there. In the early 1940s, the Republicans moved almost even with the Democrats before slipping back.

"The fact is the Democrats themselves don't know what to do," Ladd says. "It is intellectual self-doubt more than massive shifts in public views or allegiances that lies behind the Democrat leadership's failure."

Democratic alternatives exist, but not the will to rally behind them. MIT economist Lester Thurow, for example, suggests dropping taxes on savings, changing capital gains laws, and altering social security and veterans benefits in lieu of the Reagan program.